88 



Annual Report of the Entomologist of the New Jersey Experiment Station. — 

 Prof. J. 1>. Smith's Annual lloport as Entomologist of the Agricultural 

 Experiment Station of New Jersey has just been pul)lishecl as au au- 

 thor's extra from the Annual Report of the Station for 1890. The re- 

 port includes a reconsideration of the different topics which have been 

 treated in the bulletins published from time to time during the year? 

 together with a few additional notes on insects of less importance than 

 those treated in the bulletins. A most interesting appendix to this re- 

 port is a series of chemical tests, mainly with London purple, Paris 

 green, and white arsenic, made by the chemist of the New Jersey Sta- 

 tion. These tests were undertaken with a view of indicating the exact 

 proportions of lime and water to be added to the arsenical mixtnres to 

 prevent the burning of the foliage of the plants treated, and were sug- 

 gested by certain statements made by Mr. Grillette, of the Colorado Sta- 

 tion. It was found that the object of adding the lime water was to take 

 up the soluble arsenic and unite with it in the form of normal calcium 

 arseuite, which is insoluble in water. The amount of arsenious oxide 

 in London purple varies considerably in different samples, but for ordi- 

 nary use it is recommended that a mixture of one pound of London pur- 

 ple to three-fourths of a pound of fresh lime be thoroughly mixed in one 

 gallon of hot water and allowed to digest about two hours. If the water 

 can be conveniently kept hot during the entire time, it will be advisable 

 to do so. Water can then be added in siTfficien't quantities to bring it 

 to the desired strength, and it will be found that, with the average 

 sample of the purple, the soluble arsenic has been taken up by the lime. 

 In Paris green there is a very small amount of soluble arsenic — in one 

 sample only 0.4 per cent was found. This small quantity can be readily 

 rendered insoluble by the addition of a small quantity of lime when 

 mixing. With white arsenic, a substance Avhich we have only been 

 able to use with cold water, without injury to the trees, experiments 

 show that, by the addition of lime in the proportion of 1.5 parts by 

 weight to 1 part of the arsenious oxide, aU of the soluble arsenic will be 

 made insoluble. 



Bacterial Disease of the Chinch Bug. — We have jUSt received from Prof. 

 S. A. Forbes, State entomologist of Illinois, a copy of his i^aper entitled, 

 " On a Bacterial Insect Disease," reprinted from the September num- 

 ber of the North American Practitioner. The disease, Micrococcus in- 

 sectorum Burrill, is confined to a single portion of the digestive tract, 

 which is fully described. The closing remarks, particularly the para- 

 graph bearing upon the economic value of the disease, are specially 

 interesting and conform so closely to our own view^s in the mattei", and 

 have such an important bearing on Prof. Snow's work, that we quote 

 them entire: 



Concerniug the utilization of artificial cultures of Microccocus for a propagation 

 of this disease amoug insects not affected, I am at present able to say but little, as 

 I have not yet succeeded, in either season when it was common, iu finding lots of 



